The following is taken directly from the Connecticut State Department of Revenue Services website:
"If one spouse is a nonresident of Connecticut who has Connecticut source
income and is required to file a Connecticut income tax return and the
other is a nonresident with no Connecticut source income, the nonresident spouse with Connecticut source income must file a Connecticut income tax return as filing separately for Connecticut only if they file a joint federal return. The spouses may file a joint Connecticut income tax return only if they both consent to be treated as Connecticut nonresidents with Connecticut source income. The nonresident spouse with Connecticut source income is required to file a Connecticut income tax return
if his or her share of federal adjusted gross income exceeds $12,000
or, even if his or her share is $12,000 or less if he or she had any
Connecticut income tax withheld from wages or payments."
Source: https://portal.ct.gov/DRS/Individuals/Individual-Tax-Page/Nonresident-Working-in-Connecticut
So, it appears that if you file your federal income tax return as MFJ, you are
permitted to file your Connecticut return MFJ also, as long as your file consents to the jurisdiction of the Connecticut DRS. Since she has no income to which DRS could claim taxing jurisdiction, there is no liability attached to making this consent.
